<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        #c1{
            font-size: 50px; 
            color: blue;
            font-weight: 400;
            font-style: italic;
        }
        /* 字体居中字体大小与边框大小呈四倍关系 */
        #c2{
            width: 400px;
            height: 400px;
            font-size: 100px;
            border: 1px solid yellow;
            text-align: center;
            line-height: 400px;
        }
        .a{
            text-align: center;
        }
    </style>
</head>
<body>
    <p id="c1" class="a">Lorem ipsum dolor sit amet consectetur, adipisicing elit. Labore exercitationem reiciendis temporibus tenetur adipisci modi sunt natus harum consequuntur aperiam dolor, sequi quas pariatur autem officiis doloremque in! Nesciunt, recusandae?</p>
    <div id="c2">bbb</div>
</body>
</html>